Long ago, the blood of a simple slave was used in an experiment which created a strange, shapeless being. In exchange for the gift of existence, the being gave the slave a name - and cursed him with immortality.

After investigating the twisted roots of the Bradley family tree, Mustang gathers his most loyal troops. Meanwhile, Ed and his allies continue fighting Selim, who shocks everyone by turning on his own kind.

As the light of the sun vanishes, Mustang learns the loss which comes from seeing the other side of the Gateway - and five sacrifices gather in the dark presence of the Father.

When the battle ends, the one known as Father meets his final fate beyond the Gateway. When the one known as Fullmetal enters the sacred space, he finds only the promise of a new beginning.